As such a type of disk drive, a disk drive that has an opening on the front panel through which a disk tray opens and closes, and after the tray is opened and a disk is loaded onto the tray, the tray is automatically retracted into a predetermined position (a mounted position onto the turn table) in the disk drive is well known.
In such a type of disk drive, when a disk is loaded into this type of disk drive it is held between the turntable and a clamp and driven at a specific rotational speed so that data signals recorded to the disk can be read by the disk drive, that is recording or reproducing apparatus, during a read operation, for example. More specifically, signals are recorded to tracks within a specific area of the disk, and an optical pickup for signal reading is driven according to the track address of the desired signal so that the desired signal can be reproduced.
This type of disk drive has following three basic operations that require drive motor power: disk loading whereby the tray is driven in two directions between a disk loading/unloading position outside the disk drive at which a disk can be placed on or removed from the tray, and a loading/unloading position inside the disk drive at which the disk is loaded to or unloaded from the turntable; disk driving whereby the turntable is driven to spin a disk; and pickup driving whereby an optical pickup is driven primarily between positions at the outside circumference and inside circumference of the disk.
Conventionally, typical disk drives have also used separate motors (that is, three individual motors) as the drive source for these three operations.
In view of to this problem, in Japanese Utility Model Laid-Open Publication No. 3-49682 (hereinafter referred to as prior art 1), for example, a disk player (disk drive) is suggested that reduces the number of required motors to two by driving a single loading motor in forward and reverse directions for disk loading and unloading, disk chucking, and pickup drive.
A constitution according to the prior art 1 typically comprises a case and a chassis substantially integrated with the case, a turntable and a drive motor thereof are fixed to the chassis. That is, because the vertical position of the turntable is fixed, the disk must be moved vertically for disk loading and unloading in order to avoid interference with the turntable. In addition, the clamper side (chucking plate) must be driven vertically in order to clamp (settle) the disk to the turntable.
Therefore, in the disk drive according to the prior art 1, a disk holder for lifting the disk from the disk holding surface of the tray is provided, and rotating up or down the disk holder timed to the tray movement, thereby interference between the disk and turntable during disk loading and unloading is to be avoided. A chucking plate is further provided, that is supported by the fixed chassis through a chucking arm, so that the chucking plate can rotate and move vertically. And, the chucking plate is rotated up or down according to the disk loading and unloading timing to either clamp the disk to the turntable or to release the disk. Drive construction and operating the component parts are thus quite complicated and disadvantageous with respect to simplifying drive construction and achieving good stable operation.
Furthermore, all drive parts other than the tray and associated drive system are also provided on the fixed chassis in the disk drive according to the prior art 1. In addition, these parts are rigidly attached or supported on the fixed chassis. As a result, any impact, shock, or vibration to which the disk player is exposed is also transmitted directly from the fixed chassis to the various rigidly attached drive parts. These parts are thus easily susceptible to major damage. This design is therefore disadvantageous with respect to improving the durability of the disk drive to the effects of external forces, that is, resistance to shock and vibration.
Rigid attachment of these components to the fixed chassis also makes it necessary to extremely precisely position these components relative to each other. Extremely high precision is therefore required in both parts manufacture and assembly. When the need to mass-produce these components is considered, this need for extremely high precision is disadvantageous with respect to increasing productivity.
Considering these problems of the prior art, the applicant of this application has suggested, in Japanese Patent Application No. 11-23833 (hereinafter referred to as prior art 2), an optical disk drive having a basic constitution that has a first base (drive base) comprising a base frame of the disk drive, and a second base (traverse base) separate from the first base and supported to move or swing vertically relative to the first base, and has disposed thereto the turntable and a first motor for rotationally driving the turntable, and the optical pickup and pickup drive mechanism. This optical disk drive is able to reduce the number of motors used for drive operation, simplify the construction, improve the durability against shock and vibration, and improve the productivity.
According to this optical disk drive, the second base is supported by the first base, through floating bushings at right and left two portion of one end side, and through a gear (cam gear) supported by a floating collar and a floating spring at the other end side, in a manner enabling the second base to float (in a floating state) within specific limits (that is, within the flexibility limits of the floating bush, the floating collar and the floating spring. It is to be noted that the above-mentioned two floating bushings also have a supporting function for supporting the second base to move or swing vertically relative to the first base.
That is, the second base is not supported by a rigid construction (rigidly) on the first base, but is instead supported so as to float on the first base within limits determined by the flexibility of the damping members (the floating bushing, the floating collar and the floating spring). As a result, strong shocks or vibrations to which the optical disk drive is exposed can be absorbed by the damping members, and thus prevented from being transferred directly from the first base to drive parts on the second base. This means that the durability of the disk drive can be improved with respect to shock and vibration.
Furthermore, by supporting the second base so that it can float on the first base within the range of damping member flexibility, it is possible to adjust the relative positions of components on the first base and second base within the floating range of the second base. Compared with a conventional disk drive in which the components are supported by a rigid construction (rigidly), it is therefore possible to require less precision in parts manufacture and assembly, and productivity can therefore be improved in the manufacturing process.